RSM Vol 05 - How To Restring Dial Cords And Set Push Buttons

This 1947 training manual from the National Radio Institute provides a practical guide for technicians on repairing dial-drive mechanisms and configuring automatic tuning systems in vintage radios. The text begins by illustrating the mechanical differences between belt drives and cord drives, offering troubleshooting advice for common issues like slipping cords, broken springs, or sticking pointers. It emphasizes the importance of using diagrams and specific measurements when restringing these delicate systems to ensure accurate frequency display. The second half of the booklet focuses on setting push buttons, detailing the calibration of electrical trimmers and the adjustment of mechanical rocker-bar or cam-and-lever assemblies. Throughout the document, the author provides step-by-step servicing methods intended to help repairmen handle frequent maintenance tasks with confidence and precision. The manual concludes with tips for final testing and demonstrating the completed repairs to customers to build professional goodwill.